Cable TV

As Stacy said in the video, the average cost of cable is about $100 a month right now. And it's still rising. A recent study by consumer research firm NPD Group says it "expects the average pay-TV bill to reach $123 by the year 2015 and $200 by 2020."

I canceled my cable about six months ago and haven't looked back. I keep up on the TV shows I like with Netflix ($9.99 per month for streaming) and Hulu (free for basic, $7.99 per month for extended). Many networks also stream their shows on their websites. For example:

Bottled Water

A 16-ounce bottle of water costs about $1.50 at my local gas station. Buy a bottle of water five days a week, and you'll spend $30 a month and $360 a year.

While it's not really free, water from your tap is much cheaper. If you hate the taste - and I do - you can buy a water-filtration system for as little as $20. Check out Consumer Reports' Water filters: green buying guide 2/12.

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Credit Card Interest

If you're not paying your credit card balance off in full each month, you're wasting money on interest. If you carry a $1,000 balance on a card that charges 18 percent, you'll waste $180 every year just on interest.